You’ll have 6 months validity remaining when you check in to travel TO Thailand, so you’ll be good for that sector. If your return sector is directly from Thailand to your home (passport issuing) country, you should be OK, however if you’re flying via anywhere else, that respective country may not permit you to travel. I would recommend caution, and renew your passport. You could also check with your chosen airline. Good luck.
So sorry for your loss Tony. You did the best you can, so try not to beat yourself up. On your question regarding being better off in Thailand … this country, while it does have excellent medical facilities, is extremely slow. Given the cultural aversion to bad news, windows of opportunity are often missed. So, no.
My partner and I stayed in Away Chiang Mai Thapae Resort twice during March (a total of around 14 nights). It is a very comfortable boutique hotel with great service, nice large rooms and only 10 minutes walk from Tha Pae Gate (just far enough away to be nice and quiet at night). We stayed in one of the ground level direct pool access rooms, which was a nice bonus. If you are driving a car, they also have plenty of parking. We will definitely stay there again when we next visit Chiang Mai. Happy trails.